{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:33:28Z","timestamp":1760060008616,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,7,26]],"date-time":"2025-07-26T00:00:00Z","timestamp":1753488000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Institute of Physics Belgrade, University of Belgrade"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Data"],"abstract":"<jats:p>Localized ionization enhancements (LIEs) in altitude range corresponding to the D-region ionosphere, disrupting Very-Low-Frequency (VLF) signal propagation. This case study focuses on Lightning-induced Electron Precipitation (LEP), analyzing amplitude and phase variations in VLF signals recorded in Belgrade, Serbia, from worldwide transmitters. Due to the localized, transient nature of Energetic Electron Precipitation (EEP) events and the path-dependence of VLF responses, research relies on event-specific case studies to model reflection height and sharpness via numerical simulations. Findings show LIEs are typically under 1000 \u00d7 500 km, with varying internal structure. Accumulated case studies and corresponding data across diverse conditions contribute to a broader understanding of ionospheric dynamics and space weather effects. These findings enhance regional modeling, support aerosol\u2013electricity climate research, and underscore the value of VLF-based ionospheric monitoring and collaboration in Europe.<\/jats:p>","DOI":"10.3390\/data10080121","type":"journal-article","created":{"date-parts":[[2025,7,28]],"date-time":"2025-07-28T07:57:24Z","timestamp":1753689444000},"page":"121","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Investigating Mid-Latitude Lower Ionospheric Responses to Energetic Electron Precipitation: A Case Study"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4769-0152","authenticated-orcid":false,"given":"Aleksandra","family":"Kolarski","sequence":"first","affiliation":[{"name":"Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7938-5748","authenticated-orcid":false,"given":"Vladimir A.","family":"Sre\u0107kovi\u0107","sequence":"additional","affiliation":[{"name":"Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7785-4456","authenticated-orcid":false,"given":"Zoran R.","family":"Miji\u0107","sequence":"additional","affiliation":[{"name":"Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Filip","family":"Arnaut","sequence":"additional","affiliation":[{"name":"Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,26]]},"reference":[{"key":"ref_1","unstructured":"Kelley, M.C. (2009). The Earth\u2019s Ionosphere, Elsevier."},{"key":"ref_2","unstructured":"Pr\u00f6lss, G. (2012). Physics of the Earth\u2019s Space Environment: An Introduction, Springer Science & Business Media."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Bychkov, V., Golubkov, G., and Nikitin, A. (2010). Atmosphere\u2013Ionosphere Electrodynamic Coupling. The Atmosphere and Ionosphere: Dynamics, Processes and Monitoring, Springer.","DOI":"10.1007\/978-90-481-3212-6"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1202","DOI":"10.1007\/s11434-010-4226-9","article-title":"Solar activity effects of the ionosphere: A brief review","volume":"56","author":"Liu","year":"2011","journal-title":"Chin. Sci. Bull."},{"key":"ref_5","first-page":"123","article-title":"Ionosphere and radio communication","volume":"22","author":"Bora","year":"2017","journal-title":"Reson. J. Sci. Educ."},{"key":"ref_6","unstructured":"McMorrow, D. (2011). Impacts of Severe Space Weather on the Electric Grid, The MITRE Corporation."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Pirjola, R. (2007). Space weather effects on power grids. Space Weather-Physics and Effects, Springer.","DOI":"10.1007\/978-3-540-34578-7_10"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Kouck\u00e1 Kn\u00ed\u017eov\u00e1, P., La\u0161tovi\u010dka, J., Kouba, D., Mo\u0161na, Z., Podolsk\u00e1, K., Potu\u017en\u00edkov\u00e1, K., \u0160indel\u00e1\u0159ov\u00e1, T., Chum, J., and Rusz, J. (2021). Ionosphere influenced from lower-lying atmospheric regions. Front. Astron. Space Sci., 8.","DOI":"10.3389\/fspas.2021.651445"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Giannattasio, F. (2022). Ionosphere Monitoring with Remote Sensing. Remote Sens., 14.","DOI":"10.3390\/books978-3-0365-5904-9"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Barta, V., Natras, R., Sre\u0107kovi\u0107, V., Koronczay, D., Schmidt, M., and \u0160ulic, D. (2022). Multi-instrumental investigation of the solar flares impact on the ionosphere on 05\u201306 December 2006. Front. Environ. Sci., 10.","DOI":"10.3389\/fenvs.2022.904335"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Shindin, A.V., Moiseev, S.P., Vybornov, F.I., Grechneva, K.K., Pavlova, V.A., and Khashev, V.R. (2022). The Prototype of a Fast Vertical Ionosonde Based on Modern Software-Defined Radio Devices. Remote Sens., 14.","DOI":"10.3390\/rs14030547"},{"key":"ref_12","unstructured":"Hunsucker, R.D. (2013). Radio Techniques for Probing the Terrestrial Ionosphere, Springer Science & Business Media."},{"key":"ref_13","first-page":"146","article-title":"VLF\/LF sounding of the lower ionosphere to study the role of atmospheric oscillations in the lithosphere-ionosphere coupling","volume":"15","author":"Molchanov","year":"2001","journal-title":"Adv. Polar Up. Atmos. Res."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1016\/0021-9169(93)90122-F","article-title":"Experimental daytime VLF ionospheric parameters","volume":"55","author":"Thomson","year":"1993","journal-title":"J. Atmos. Terr. Phys."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Kolarski, A., Veselinovi\u0107, N., Sre\u0107kovi\u0107, V.A., Miji\u0107, Z., Savi\u0107, M., and Dragi\u0107, A. (2023). Impacts of Extreme Space Weather Events on September 6th, 2017 on Ionosphere and Primary Cosmic Rays. Remote Sens., 15.","DOI":"10.3390\/rs15051403"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Ogunsua, B.O., Qie, X., Srivastava, A., Abe, O.E., Owolabi, C., Jiang, R., and Yang, J. (2023). Ionospheric Perturbations Due to Large Thunderstorms and the Resulting Mechanical and Acoustic Signatures. Remote Sens., 15.","DOI":"10.3390\/rs15102572"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"RS0A17","DOI":"10.1029\/2008RS004029","article-title":"A brief review of \u201csolar flare effects\u201d on the ionosphere","volume":"44","author":"Tsurutani","year":"2009","journal-title":"Radio Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"445","DOI":"10.1016\/j.jastp.2005.04.009","article-title":"Electrical processes coupling the atmosphere and ionosphere: An overview","volume":"68","author":"Rycroft","year":"2006","journal-title":"J. Atmos. Sol.-Terr. Phys."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1016\/S1364-6826(96)00048-X","article-title":"On the numerical modelling of the VLF Trimpi effect","volume":"59","author":"Nunn","year":"1997","journal-title":"J. Atmos. Sol.-Terr. Phys."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1016\/S1364-6826(00)00004-3","article-title":"Trimpi perturbations from large ionisation enhancement patches","volume":"62","author":"Nunn","year":"2000","journal-title":"J. Atmos. Sol.-Terr. Phys."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2296","DOI":"10.1002\/jgra.50264","article-title":"Energetic electron (>10 keV) microburst precipitation, ~5\u201315 s X-ray pulsations, chorus, and wave-particle interactions: A review","volume":"118","author":"Tsurutani","year":"2013","journal-title":"J. Geophys. Res. (Space Phys.)"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"01005","DOI":"10.1051\/e3sconf\/202019601005","article-title":"Energetic electron precipitation and their atmospheric effect","volume":"196","author":"Mironova","year":"2020","journal-title":"E3S Web Conf."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1595","DOI":"10.1109\/TPS.2022.3208906","article-title":"Space Plasma Physics: A Review","volume":"51","author":"Tsurutani","year":"2023","journal-title":"IEEE Trans. Plasma Sci."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"e2024JA033639","DOI":"10.1029\/2024JA033639","article-title":"Lightning-Induced Electron Precipitation Events Observed at Low Altitudes","volume":"130","author":"Linzmayer","year":"2025","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_25","first-page":"10130","article-title":"Heliospheric plasma sheet (HPS) impingement onto the magnetosphere as a cause of relativistic electron dropouts (REDs) via coherent EMIC wave scattering with possible consequences for climate change mechanisms","volume":"121","author":"Tsurutani","year":"2016","journal-title":"J. Geophys. Res. (Space Phys.)"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"407","DOI":"10.1007\/s10712-016-9396-9","article-title":"On the Use of VLF Narrowband Measurements to Study the Lower Ionosphere and the Mesosphere\u2013Lower Thermosphere","volume":"38","author":"Silber","year":"2017","journal-title":"Surv. Geophys."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Sre\u0107kovi\u0107, V.A., \u0160uli\u0107, D.M., Ignjatovi\u0107, L., and Vuj\u010di\u0107, V. (2021). Low ionosphere under influence of strong solar radiation: Diagnostics and modeling. Appl. Sci., 11.","DOI":"10.3390\/app11167194"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"e2022EA002460","DOI":"10.1029\/2022EA002460","article-title":"A method for imaging energetic particle precipitation with subionospheric VLF signals","volume":"10","author":"Gasdia","year":"2023","journal-title":"Earth Space Sci."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"233","DOI":"10.5194\/ars-13-233-2015","article-title":"Remote sensing and modeling of energetic electron precipitation into the lower ionosphere using VLF\/LF radio waves and field aligned current data","volume":"13","author":"Schmitter","year":"2015","journal-title":"Adv. Radio. Sci."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Fu, T., Wu, Z., Hu, P., and Zhang, X. (2021). Fluctuation of Lower Ionosphere Associated with Energetic Electron Precipitations during a Substorm. Atmosphere, 12.","DOI":"10.3390\/atmos12050573"},{"key":"ref_31","unstructured":"Buz\u00e1s, A., Barta, V., Steinbach, P., and B\u00f3r, J. (2017, January 23\u201328). Impact of local environmental conditions on atmospheric electrical potential gradient measurements. Proceedings of the EGU General Assembly Conference Abstracts, Vienna, Austria."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"e2020JA028540","DOI":"10.1029\/2020JA028540","article-title":"Quantification of ionospheric perturbations from lightning using overlapping paths of VLF signal propagation","volume":"126","author":"Renick","year":"2021","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1595","DOI":"10.1016\/j.asr.2014.02.022","article-title":"Sensing the Earth\u2019s low ionosphere during solar flares using VLF signals and goes solar X-ray data","volume":"53","author":"Kolarski","year":"2014","journal-title":"Adv. Space Res."},{"key":"ref_34","unstructured":"Ferguson, J. (1998). Computer Programs for Assessment of Long-Wavelength Radio Communications, Version 2.0. Users Guide and Source Files, Space and Naval Warfare Systems Center. Technical Document 3030."},{"key":"ref_35","unstructured":"LWPC (2025, May 30). Computer Programs for Assessment of Long-Wavelength Radio Communications, V2.1. Available online: https:\/\/github.com\/space-physics\/LWPC."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Sre\u0107kovi\u0107, V.A., \u0160uli\u0107, D.M., Vuj\u010di\u0107, V., Miji\u0107, Z.R., and Ignjatovi\u0107, L.M. (2021). Novel Modelling Approach for Obtaining the Parameters of Low Ionosphere under Extreme Radiation in X-Spectral Range. Appl. Sci., 11.","DOI":"10.3390\/app112311574"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"565","DOI":"10.1007\/s12036-015-9361-x","article-title":"Comparative Analysis of VLF Signal Variation along Trajectory Induced by X-ray Solar Flares","volume":"36","author":"Kolarski","year":"2015","journal-title":"J. Astrophys. Astron."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"106074","DOI":"10.1016\/j.jastp.2023.106074","article-title":"Lower-ionosphere electron density and effective recombination coefficients from multi-instrument space observations and ground VLF measurements during solar flares","volume":"247","author":"Dominique","year":"2023","journal-title":"J. Atmos. Sol.-Terr. Phys."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"763","DOI":"10.1016\/j.asr.2013.12.026","article-title":"Response of the Earth\u2019s lower ionosphere to the Ground Level Enhancement event of December 13, 2006","volume":"53","author":"Kudela","year":"2014","journal-title":"Adv. Space Res."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Kolarski, A., Sre\u0107kovi\u0107, V.A., and Miji\u0107, Z.R. (2022). Response of the Earth\u2019s Lower Ionosphere to Solar Flares and Lightning-Induced Electron Precipitation Events by Analysis of VLF Signals: Similarities and Differences. Appl. Sci., 12.","DOI":"10.3390\/app12020582"}],"container-title":["Data"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2306-5729\/10\/8\/121\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:16:31Z","timestamp":1760033791000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2306-5729\/10\/8\/121"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,7,26]]},"references-count":40,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2025,8]]}},"alternative-id":["data10080121"],"URL":"https:\/\/doi.org\/10.3390\/data10080121","relation":{},"ISSN":["2306-5729"],"issn-type":[{"type":"electronic","value":"2306-5729"}],"subject":[],"published":{"date-parts":[[2025,7,26]]}}}